A. Back flow of fluid in the event of stoppage of pump
B. Discharge pressure
C. Flow of liquid during operation of the pump
D. All A., B. and C.
Related Mcqs:
- A 2″ gate valve fitted in a pipe is replaced by a similar globe valve. Pressure drop in gate valve was Δp. For the same discharge, the pressure drop across globe valve is__________________?
A. Δp
B. < Δp
C. > Δp
D. Δp2 - Foot valve provided in the pump is a ______________ valve?
A. Direction control
B. Back pressure
C. Relief
D. Pressure reduction - Consider a centrifugal pump having a specific impeller diameter, fixed impeller speed pumping a liquid of constant density at a particular discharge capacity. With decrease in the capacity of the pump, the _______________ decreases?
A. NPSH required
B. BHP required by the pump
C. Head of the liquid pumped
D. All A., B. and C. - A centrifugal pump is used to pump water through a horizontal distance of 150 m, and then raised to an overhead tank 10 m above. The pipe is smooth with an I.D of 50 mm. What head (m of water) must the pump generate at its exit E. to deliver water at a flow rate of 0.001 m3/s? The Fanning friction factor, f is 0.0062 ?
A. 10 m
B. 11 m
C. 11.8 m
D. 30 m - A centrifugal pump used to pump water is used to pump an oil with specific gravity of 0.8 at the same rate. The power consumption will now_________________?
A. Increase
B. Decrease
C. Remain same
D. Data insufficient to predict - A centrifugal pump designed to pump water is employed to pump a more viscous oil. In the later case, the pump_________________?
A. Develops a lower head
B. Capacity is reduced
C. Requires more power
D. All A., B. and C. - The vent valve provided in a liquid handling centrifugal pump is___________________?
A. Generally a needle valve
B. Used to release any gases that might be vapour locking the pump
C. Helpful in easy removal of samples
D. All A., B. and C. - For the same terminal conditions and valve size, the pressure drop in a fully opened globe valve as compared to that in a gate valve is___________________?
A. More
B. Less
C. Equal
D. Either A. or B.; depends on the viscosity of the fluid - While starting a centrifugal pump, its delivery valve should be kept___________________?
A. Opened
B. Closed
C. Either opened or closed; it does not make any difference
D. Either opened or closed; depending on the fluid viscosity - Foot valves are provided in the suction line of a centrifugal pump to ____________________?
A. Avoid priming, every time we start the pump
B. Remove the contaminant present in the liquid
C. Minimise the fluctuation in discharge
D. Control the liquid discharge
